Tool for removing a rocker stud and for substituting a new one



E. A. GLOOR July 11, 1967 TOOL FOR REMOVING A ROCKER STUD AND FOR SUBSTITUTING A NEW ONE 2 Sheets-Sheet 1 Filed Sept. 14. 1965 INVENTOR EMIL A. GLOOR ATTORNEY E. A. GLOOR July 11, 1967 TOOL FOR REMOVING A ROCKER STUD AND FOR SUBSTITUTING A NEW ONE Filed Sept. 14, 1965 2 Sheets-Sheet? INVENTOR v EMIL A.GL.OOR

ATTORNEY United States Patent 3,330,024 TOQL FOR REMOVING A ROCKER STUD AND FOR SUBSTITUTING A NEW ONE Emil A. Gloor, New Milford, N.Y. (96 th Ave., Hawthorne, NJ. 07506) Filed Sept. 14, 1965, Ser. No. 487,143 3 Claims. (Cl. 29271) This invention relates to an improved automotive too], more particularly to a simple unit adapted to effectively withdraw and replace force fit elements of internal combustion engines.

A salient object of the invention is to provide a simple rugged mechanical unit which is adapted to greatly facilitate the removal and replacement of component elements of the cylinder head of an internal combustion engine which are subjected to constant wear and consequent misalignment conducing to malfunction of the component. A typical, illustrative example of such components are, for example, the press-fitted studs of rocker arm assemblies of the valves of an internal combustion engine. As is known, such studs provide a mounting on which the rocker arm or tappet cyclically and regularly depresses a spring biased valve, such as an exhaust valve during the operation of the engine. Under the recurrent thrust of the rocker arm and wear incident to continuous operation such studs which, in conventional engines are press-fitted into the cylinder head, tend to loosen in their bore and require replacement.

A further object of the invention is to provide a tool which will enable the user thereof to re-align a stud which has been press-fitted into an engine head at the factory, but in actuality, the press-fitted stud is not in a true vertical alignment as it should be and by employing the tool of the instant invention, the stud, when removed for replacement with a new stud can set in a true vertical alignment, thereby obviating the rocker arm from riding oil the valve stem when the engine is in operation.

It is a known fact that under certain conditions the stud which has been presumably press-fitted within the engine head at the factory will under severe working conditions work itself out of its bore and when this occurs the tool of the instant invention is employed for removing the defective stud and enables one to use a tapping tool so as to form threads in the engine head which will accommodate a replacement stud which is externally threaded and will enable the placement stud to be in true vertical alignment.

As will be seen, the instant invention consists of a tool in the form of a metallic, rectangular or oblong casing of predetermined thickness, having spaced circular openings, a distance apart from center line to center line equal to the spacing of the press-fitted studs on which the valve rockers of an internal combustion engine are mounted. Each of these openings contains a cylindrical element having an internal diameter matching the outer diameter of the stud received therein. These cylindrical elements are keyed to the casing so that they can not rotate therein but are allowed a slight slidable movement for a purpose described hereinafter. The free ends of the studs are threaded and extend above the casing and nuts are used thereon to maintain and immobilize the casing in place on top of the engine block. The nut on the threaded portion of the stud to be removed is threaded further downwardly until the stud is forced from its socket. This is possible because the casing is immobilized as stated above. The cylindrical elements which receive the studs are threaded so that a tap may be driven therethrough and into the engine block to cut a proper thread therein so that a new stud may be placed therein in the event that the stud removed is bent or otherwise damaged.

3,330,024 Patented July 11, 1967 In order to enable a ready comprehension of the invention, a preferred embodiment, to be described in detail, is shown in the accompanying drawing in which:

FIG. 1 is an isometric view of the novel tool unit of the invention;

FIG. 2 is a top plan view of a portion of the unit;

FIG. 3 is a transverse sectional view through the cylinler head of an internal combustion engine showing the .001 mounted in operative position;

FIG. 4 is a latent elevation as viewed in the direction of line 44 of FIG. 3;

FIG. 5 is a transverse view of the unit, shown partly in elevation and partially in section illustrating the manner in which a force fit stud is withdrawn from the cylinder head;

FIG. 6 is a view, similar to FIG. 4, illustrating the manner of tapping threads in an engine head.

FIG. 7 is a view, similar to FIG. 6 showing the replacement stud installed and secured in operative position in the cylinder head.

The improved tool or appliance of the invention as noted comprises a casing 1 which is adapted to be mounted on a cylinder head to simply, quickly and effectively eX- tract a worn press-fit stud and in a succeeding operation to install a screw threaded replacement stud. As shown particularly in FIG. 3, the cylinder head, indicated generally at 2 is of conventional construction. This is formed with a series of longitudinally aligned cusps or recesses 3. In each such recess is a bushing 4 for receiving a valve stem (not shown) and for seating a valve biasing spring (not shown). The cylinder head is provided with a series of longitudinally aligned apertures 5 in which the conventional valve push rods (not shown) reciprocate to abut and actuate a valve rocker arm (not shown) mounted for oscillation on stud 6, the operation of which in relation to the push rod and valve is well known and needs no further discussion.

Referring to FIGS. 1, 4, 5 and 6, unit or casing 1 preferably comprises a one piece or unitary casting or forging although in some circumstances, it may be made up of welded relatively heavy metal stampings. As shown, the unit or casing 1 is substantially rectangular in cross section and is of a length suflicient to bridge two aligned rocker arm studs (FIG. 4).

The unit or casing is formed or provided with two cylindrical bores 7 extending through the unit from top to bottom. It will be observed, as for example, in FIG. 5 that the center line distance between such bores 7 is equal to the center line distance between adjacent studs. Adjacent the upper and lower inner surface each bore 7 is cut out to provide upper and lower reentrant ledges 8 and 9 respectively for a purpose to appear.

Fitting for close sliding within each bore 7 is a cylindrical piston-like member 10 provided with an internally threaded bore 11. The upper portion of the member 10 is formed with a flat bearing surface 12 and the lower por- 7 tion is formed wtih a flat bearing surface 13. Adjacent its upper and lower end, the exterior peripheral surface of cylinder 10 is cut or grooved as at 14 and 15 respectively in which the snap rings 16 and 17 are adapted to seat. Each member 10 is provided with a vertical key 18 which is adapted for sliding engagement with a key way 19 formed in casing 1 (see FIG. 1).

The assemblage of the improved tool, its installation on a cylinder head rocker arm stud and the operation in removing worn studs and replacing such removed stud will be apparent from the foregoing description. It will be noted, at this point, that the upper and lower portions of cylinders 10 are symmetrically formed. As a result, the members 10 are identical in structure and may be used interchangeably in the two apertures of the casing 1.

1 a tive cooperating apertures in casing 1 with the key 18 of 'each unit engaging in the corresponding key way 19. The inserted member 10 is then moved successively above the upper surface and below the lower surface of the cas- A ing and the retainer snap rings and 16 are inserted in their respective receiving grooves. As will be observed from an inspection of FIG. 6, when such rings are mounted on members 10 they are adapted to serve as a limiting stop by reason of their abutment against the base of re- To assemble this novel tool of the invention, the cylindrical members 10 are dropped or fitted into their respec- "entrant ledges 8 and 9 in casing 1. Due to the engagement of keys 18 within key ways 19 turning or'rotative move- 'ment of members 10 in the casing is precluded, hence, members 10 can move freely vertically (Within limits set by the position of the retainer rings 15 and16 and the depth of the cooperating ledges Sand 9 in the casing 1). When it is desired to replace a worn valve rocker arm stud, the stud retaining nut 22 on such stud and the nut -21 on an adjacent stud are removed. The unit or casing 1 is fitted over the ends of the studs such that the bores of the cylindrical units slide down. over the studs and the lower bearing portions rest on the top of the stud supporting extension 20 of the cylinder head.

In the event that thereis some difference in the altitude or horizontal planes of the upper faces of stud supports 20, as shown in exaggerated form in FIGS. 4 to 6 inclusive, one or the other of the cylinders 10 will move by gravity into contact with the stud support of lower elevation and this contact coupled with the relatively close fit and extended contact of the member 10 with the external surface of the stud serves to establish and maintain the casing in a true horizontal position and normal to the axis of the stud and hence, a force exerted on the casing and stud will be applied directly in the plane of the axis of the stud.

After the casing is emplaced on the adjacent studs in 'the manner described, stud nuts 21 and 22 are screwed j down to seat the casing firmly on stud supporting projections 20. Thereafter (assuming that the stud shown in the right portion of FIG. 5 is to be extracted), stud nut V 22 is rotated by a suitable tool in the direction of the 9 arrow. Under this action, operating on the stud and against 'the immovable cylinder block, the stud is readily and 'completely extracted from the press fit in the cylinder "head. i

A salient feature of the invention, as previously noted is to use the novel unit, subsequent to the removal of a worn rocker arm stud, to facilitate the attachment of a 'replacement'stud'As is depicted in FIGS. 5 and 6, after the worn stud has been removed and while casing 1 with cylinder 10 in position, a tap 23 is inserted in the threaded bore 11 of cylinder 10. The pitch and depth of the screws of such tap are the same as that of the internally threaded bore 11. The tap is rotatedin the direction of the arrow (FIG. 6) by means of any suitable tool and into screw threaded engagement with the threaded bore 11 of similar profile in the bore. Since the cylinder 10 is restrained from rotation by the key 18 and key way 19, the tap readily moves downwardly through cylinder 10 and makes cutting or tapping engagement with the smooth walls 24 of the stud socket 26. After tapping has been conducted to the desired extent, the tap is unscrewed, a new stud 25 having a 9W threaded sectionis inserted inthe bore of cylinder 10 and screwed home through the threaded bore 11 and into the cylinder head.

After emplacing such new stud 25, the retaining nut are interchangeable thus facilitating replacements and/or 7 repair. The materials of which the unit is constructed area readily available 'and economical. As noted, the casing 1 may be a metal casting, forging or stamping. The casing, if desired, can be constructed of compression molded or otherwise formed strong and durable plastics such as phenolics, epoxies and the like. The invention among other things provides a cheap, economical garage tool to simply perform a heretofore difiicult replacement of worn valve rocker arm studs since it obviates the necessity of using heavy expensive equipment required for force pressing such studs.

While a preferred modification of the invention has been described, it is to be understood that this is given to exemplifythe underlying principles ot'the invention and not as limiting its scope short of such limitations as are imposed by the appended claims. I. claim:

1. A tool for removing one of aligned studs press-fitted in an engine block, wherein the studs have athreaded portion protruding above the engine block, said tool consist? ing of an elongated casing having transverse cylindrical apertures the axes of which are spaced apart a distance equal to the spacing of themes of the studs, a cylindrical hollow element in each of the cylindrical apertures V adaptedto individually engage the studs, means for locking the said elements in said apertures to prevent independent rotation thereof, means for seating the casing firm- 1y on the engine block with adjacent studs receivedjn adjacent hollow elements, said means including the threads on the adjacent studs and a nut on each of the threaded portions of the studs pressing against the tool, the continued screwing of said nuts forcing the removal of the selected stud from the engine block.

2. A tool as set forth in claim l, where the hollow elements are slidable in opposite direction within their. respective cylindrical apertures, and means for limiting suchmovement in either direction.

3. A tool as set forth in claim 1 in combination with means for replacing the removed stud with a new one, said means including internal threads 'within the hollow elements and co-extensive threads in the engine block, to receive threaded stud.

References Cited.

UNITED STATES PATENTS 1,959,254 5/1934 Zerk '29- 235 X 7 2,381,062 8/1945 Krisch 29 -465 X 2,770,032 11/1956 Kelly 297-235 MYRON C. KRUSE, Primary Examiner. 

1. A TOOL FOR REMOVING ONE OF ALIGNED STUDS PRESS-FITTED IN AN ENGINE BLOCK, WHEREIN THE STUDS HAVE A THREADED PORTION PROTRUDING ABOVE THE ENGINE BLOCK, SAID TOOL CONSISTING OF AN ELONGATED CASING HAVING TRANSVERSE CYLINDRICAL APERTURES THE AXES OF WHICH ARE SPACED APART A DISTANCE EQUAL TO THE SPACING OF ONE EXES OF THE STUDS, A CYLINDRICAL HOLLOW ELEMENT IN EACH OF THE CYLINDRICAL APERTURES ADAPTED TO INDIVIDUALLY ENGAGE THE STUDS, MEANS FOR LOCKING THE SAID ELEMENTS IN SAID APERTURES TO PREVENT INDEPENDENT ROTATION THEREOF, MEANS FOR SEATING THE CASING FIRMLY ON THE ENGINE BLOCK WITH ADJACENT STUDS RECEIVED IN ADJACENT HOLLOW ELEMENTS, SAID MEANS INCLUDING THE THREADS ON THE ADJACENT STUDS AND A NUT ON EACH OF THE THREADED 